Please add function to populate person-column by assignees to another person-column

I have many different use cases where this is needed.
Just one example for clarification:

I want the person responsible for an item to be assigned to a subitem when the status changes to “review”.

So far a workaround would be to set up an automation for every single person in the agency which includes two triggers:

When Status changes
and only if person is someone

I could then choose that the person who is specified in the second trigger will be the assignee.

this gets immensely time-consuming and prone to errors due to the number of people.

So why is there no way to simply use an automation like

when Status changes
assign [people column] as person

?

Please add this feature as soon as possible!